Hypoxia challenges left ventricular (LV) function due to reduced energy supply. Conflicting results exist whether high-altitude exposure impairs LV diastolic function and thus contributes to the high altitude-induced increase in systolic pulmonary artery pressure (sPAP) and reduction in stroke volume (SV). This study aimed to assess LV diastolic function, LV end-diastolic pressure (LVEDP) and LA mechanics using comprehensive echocardiographic imaging in healthy volunteers at 4559m. Fifty subjects performed rapid (<20h) and active ascent from 1130m to 4559m (high). All participants underwent echocardiography during baseline examination at 424m (low) as well as 7, 20 and 44h after arrival at high altitude. Heart rate (HR), sPAP and comprehensive volumetric- and Doppler- as well as speckle tracking-derived LA strain parameters were obtained to assess LV diastolic function, LA mechanics and LVEDP in a multi-parametric approach. Data for final analyses were available in 46 subjects. HR (low: 64+/-11 vs. high: 79+/-14 beats/min, p<0.001) and sPAP (low: 24.4+/-3.8 vs. high: 38.5+/-8.2mmHg, p<0.001) increased following ascent and remained elevated at high altitude. SV (low: 64.5+/-15.0 vs. high: 58.1+/-16.4mL, p<0.001) and EDV decreased following ascent and remained decreased at high altitude due to decreased LV passive filling volume whereas LA mechanics were preserved. There was no case of LV diastolic dysfunction or increased LVEDP estimates. In summary, this study shows that rapid and active ascent of healthy individuals to 4559 m impairs passive filling and SV of the LV. These alterations were not related to changes in LV and LA mechanics. This article is protected by copyright. All rights reserved.
- Sareban, M.
- Perz, T.
- Macholz, F.
- Reich, B.
- Schmidt, P.
- Fried, S.
- Mairbaurl, H.
- Berger, M. M.
- Niebauer, J.
Keywords
- Hypoxia
- cardiac imaging
- high altitude pulmonary edema
- speckle tracking echocardiography
